U.S. patent application number 14/594615 was filed with the patent office on 2015-10-01 for electronic device and active stylus.
The applicant listed for this patent is KABUSHIKI KAISHA TOSHIBA. Invention is credited to Nobutaka Nishigaki.
Application Number | 20150277592 14/594615 |
Document ID | / |
Family ID | 54190294 |
Filed Date | 2015-10-01 |
United States Patent
Application |
20150277592 |
Kind Code |
A1 |
Nishigaki; Nobutaka |
October 1, 2015 |
ELECTRONIC DEVICE AND ACTIVE STYLUS
Abstract
According to one embodiment, an electronic device includes a
housing, a touch panel in the housing, a power transmitter in the
housing, and an active stylus. The active stylus is capable of
receiving power wirelessly from the power transmitter. The power
transmitter includes a first coil to generate magnetic flux
orthogonal to an upper surface of the housing for transmitting
power. The active stylus includes one or more second coils for
receiving power to resonate with the magnetic flux, at least one of
the one or more second coils configured to be parallel to the first
coil when the active stylus is in a first position or in a second
position on the upper surface of the housing.
Inventors: |
Nishigaki; Nobutaka; (Tokyo,
JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KABUSHIKI KAISHA TOSHIBA |
Tokyo |
|
JP |
|
|
Family ID: |
54190294 |
Appl. No.: |
14/594615 |
Filed: |
January 12, 2015 |
Current U.S.
Class: |
345/173 |
Current CPC
Class: |
G06F 1/1698 20130101;
H02J 50/90 20160201; H02J 7/0042 20130101; G06F 3/0383 20130101;
G06F 3/03545 20130101; H02J 50/12 20160201; H02J 50/10 20160201;
G06F 2203/0384 20130101; G06F 1/266 20130101; H02J 50/40 20160201;
H02J 7/025 20130101 |
International
Class: |
G06F 3/0354 20060101
G06F003/0354; G06F 3/041 20060101 G06F003/041 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 31, 2014 |
JP |
2014-071050 |
Claims
1. An electronic device comprising: a housing; a touch panel in the
housing; a power transmitter in the housing; and an active stylus
capable of receiving power wirelessly from the power transmitter,
wherein: the power transmitter comprises a first coil to generate
magnetic flux orthogonal to an upper surface of the housing for
transmitting power; and the active stylus comprises one or more
second coils for receiving power to resonate with the magnetic
flux, at least one of the one or more second coils configured to be
parallel to the first coil when the active stylus is in a first
position or in a second position on the upper surface of the
housing.
2. The electronic device of claim 1, wherein, the active stylus
further comprises a main body portion and a clip portion wherein:
the active stylus is in the first position when both the main body
portion and the clip portion are touching on the upper surface of
the housing.
3. The electronic device of claim 2, wherein, the active stylus is
in a second position, the second position different from the first
position, when both the main body portion and the clip portion are
touching on the upper surface of the housing.
4. The electronic device of claim 1, wherein: the active stylus
receives the power generated by the first coil when the active
stylus is in the first or the second position placed on the upper
surface of the housing where the power transmitter is located in
the housing.
5. The electronic device of claim 4, the active stylus further
comprises: a shape of a prism having n faces; at least one of the
one or more second coils configured to be parallel to each of the n
faces of the prism; and at least one of the n faces intersecting
the magnetic flux, wherein the prism has n positions to be placed
on the upper surface of the housing to receive the power generated
by the first coil and n is more than or equal to three.
6. The electronic device of claim 1, the active stylus further
comprises: a secondary battery or an electric double-layer
capacitor; and a power-receiving circuit to receive power
wirelessly from the power transmitter and to charge the secondary
battery or the electric double-layer capacitor, wherein at least
one of the one or more second coils are connected to the
power-receiving circuit, and the second coils not connected to the
power-receiving circuit resonate with the second coils connected to
the power-receiving circuit.
7. The electronic device of claim 4, wherein at least one of the
one or more second coils are configured to intersect the magnetic
flux generated by the first coil when the active stylus is placed
in the first or second position on the upper surface of the housing
where the power transmitter is located in the housing.
8. An active stylus for a handwritten input operation on a touch
panel device, comprising, a power receiver to wirelessly receive
power from the touch panel device comprises one or more second
coils for receiving power by resonating with magnetic flux
generated by a first coil located in the touch panel, wherein at
least one of the one or more second coils are configured to
intersect the magnetic flux when the active stylus is in a first
position or in a second position on the touch panel device.
9. The active stylus of claim 8, further comprising a main body
portion and a clip portion, wherein the active stylus is in the
first position when both the main body portion and the clip portion
are touching on the touch panel.
10. The active stylus of claim 8, wherein the active stylus is in
the second position different from the first position when both the
main body portion and the clip portion are touching on the touch
panel device.
11. The active stylus of claim 8, wherein: the active stylus
receives the power generated by the first coil when the active
stylus is in the first or the second position placed on the touch
panel device where the first coil is located under the touch
panel.
12. The active stylus of claim 8, further comprising: a shape of a
prism having n faces; at least one of the one or more second coils
configured to be parallel to each of the n faces of the prism; and
at least one of the n faces intersecting the magnetic flux to
receive the power from the first coil when one of the n faces is
place on the touch panel device, wherein n is more than or equal to
three.
13. The active stylus of claim 8, further comprising: a secondary
battery or an electric double-layer capacitor; and a
power-receiving circuit to receive power wirelessly from the touch
panel device and to charge the secondary battery or the electric
double-layer capacitor, wherein at least one of the one or more
second coils are connected to the power-receiving circuit, and the
second coils not connected to the power-receiving circuit resonate
with the second coils connected to the power-receiving circuit.
14. The active stylus of claim 8, wherein at least one of the one
or more second coils are configured to intersect the magnetic flux
generated by the first coil when the active stylus is placed in the
first or second position on the touch panel device where the first
coil is located under the touch panel.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is based upon and claims the benefit of
priority from Japanese Patent Application No. 2014-071050, filed
Mar. 31, 2014, the entire contents of which are incorporated herein
by reference.
FIELD
[0002] Embodiments described herein relate generally to an
electronic device and an active stylus (active pen).
BACKGROUND
[0003] Recently, portable battery-driven electronic devices such as
a tablet device and a notebook personal computer (PC) have been
widespread. Such electronic devices typically comprise a
handwritten input function (stylus input function) so that a user
can perform input operation easily.
[0004] There are various types of styluses of the handwritten input
function such as an electromagnetic-type digitizer stylus, an
active or passive stylus for use with an electrostatic-type touch
panel, and a stylus for use with a resistive film-type touch
panel.
[0005] An active stylus is promising in the future since the active
stylus recently becomes more accurate and the use thereof realizes
a palm rejection function. However, an active stylus needs to be
equipped with a battery and therefore cannot be used when out of
charge.
[0006] Further, the size of a battery needs to be limited due to
the shape of a stylus. While a battery can be a primary battery, a
secondary battery and an electric double-layer capacitor, both
advantages and disadvantages exist in size, weight and battery
life. For example, by using an electric double-layer capacitor, it
is possible to make a stylus smaller in diameter and lighter but
the battery life gets shorter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] A general architecture that implements the various features
of the embodiments will now be described with reference to the
drawings. The drawings and the associated descriptions are provided
to illustrate the embodiments and not to limit the scope of the
invention.
[0008] FIG. 1 is an exemplary exterior view of a tablet device and
an active stylus constituting a wireless power-transmission system
of the embodiment.
[0009] FIG. 2 is an exemplary diagram illustrating a system
configuration of the tablet device of the embodiment.
[0010] FIG. 3 is an exemplary diagram illustrating a system
configuration of the active stylus of the embodiment.
[0011] FIG. 4 is an exemplary drawing illustrating an example where
a power-transmitting coil in the tablet device of the embodiment is
arranged.
[0012] FIG. 5 is an exemplary drawing illustrating an example where
a power-receiving coil in the active stylus of the embodiment is
arranged.
[0013] FIG. 6 is an exemplary drawing for explaining a desirable
positional relationship between the power-transmitting coil of the
tablet device and the power-receiving coil of the active stylus of
the embodiment.
[0014] FIG. 7 is an exemplary drawing for explaining a first
arrangement pattern of the power-receiving coil in the active
stylus of the embodiment.
[0015] FIG. 8 is an exemplary drawing illustrating that the active
stylus is placed on the tablet device of the embodiment.
[0016] FIG. 9 is an exemplary drawing for explaining a second
arrangement pattern of the power-receiving coil in the active
stylus of the embodiment.
[0017] FIG. 10 is an exemplary drawing for explaining a third
arrangement pattern of the power-receiving coil in the active
stylus of the embodiment.
[0018] FIG. 11 is an exemplary drawing for explaining a fourth
arrangement pattern of the power-receiving coil in the active
stylus of the embodiment.
[0019] FIG. 12 is an exemplary drawing illustrating that the active
stylus is placed in a side surface portion of the tablet device of
the embodiment.
[0020] FIG. 13 is an exemplary drawing illustrating a positional
relationship between the power-transmitting coil of the tablet
device and the power-receiving coil of the active stylus when the
active stylus is placed in the side surface portion of the tablet
device of the embodiment.
[0021] FIG. 14 is an exemplary drawing that power is transmitted
wirelessly from the tablet device to the active stylus during a
handwritten input operation of the embodiment.
DETAILED DESCRIPTION
[0022] Various embodiments will be described hereinafter with
reference to the accompanying drawings.
[0023] In general, according to one embodiment, an electronic
device comprises a housing, a touch panel in the housing, a power
transmitter in the housing, and an active stylus. The active stylus
is capable of receiving power wirelessly from the power
transmitter. The power transmitter comprises a first coil to
generate magnetic flux orthogonal to an upper surface of the
housing for transmitting power. The active stylus comprises one or
more second coils for receiving power to resonate with the magnetic
flux, at least one of the one or more second coils configured to be
parallel to the first coil when the active stylus is in a first
position or in a second position on the upper surface of the
housing.
[0024] FIG. 1 is an exemplary exterior view of a tablet device 1
and an active stylus 2 constituting the wireless power-transmission
system of the embodiment. The wireless power-transmission system
wirelessly supplies power (wirelessly transmits power) from the
tablet device 1 to the active stylus 2 by use of a magnetic field
resonant coupling mode or a direct-current-resonance mode.
[0025] As shown in FIG. 1, the tablet device 1 comprises a main
body 11 and a touch screen display 12. The touch screen display 12
is overlappingly attached to the upper surface of the main body
11.
[0026] The main body 11 has a thin box-shaped housing. The touch
screen display 12 is equipped with a flat panel display and a
sensor that detects a contact position of the active stylus 2 on
the flat panel display. The sensor is an electrostatic-type touch
panel and comprises a function to support the active stylus 2. The
flat panel display is, for example, a liquid crystal display (LCD).
The touch panel is arranged so as to cover the screen of the flat
panel display.
[0027] FIG. 2 is an exemplary diagram illustrating the system
configuration of the tablet device 1.
[0028] As shown in FIG. 2, the tablet device 1 comprises a CPU 101,
a system controller 102, a main memory 103, a graphics controller
104 and a BIOS-ROM 105. The tablet device 1 also comprises a
nonvolatile memory 106, a wireless communication device 107, an
embedded controller (EC) 108, a power-transmitting circuit for
wireless power transmission 109 and a power-transmitting coil
110.
[0029] The CPU 101 is a processor that controls the operation of
each of modules in the tablet device 1. The CPU 101 loads each of
software from the nonvolatile memory 106 to the main memory 103 and
executes it. The CPU 101 also executes a basic input/output system
(BIOS) stored in the BIOS-ROM 105. The BIOS is a program for
controlling hardware.
[0030] The system controller 102 is a device that connects the
local bus of the CPU 101 and each of components. The system
controller 102 is equipped with a memory controller that accesses
and controls the main memory 103. Also, the system controller 102
comprises a function to execute communication with the graphics
controller 104 via a serial bus conforming to the PCI EXPRESS
standard, etc.
[0031] The graphics controller 104 is a display controller that
controls an LCD 12A used as a display monitor of the tablet device
1. The LCD 12A displays a screen image based on a display signal
generated by the graphics controller 104. On the LCD 12A is
arranged a touch panel 12B. The touch panel 12B is an
electrostatic-type pointing device for performing input on the
screen of the LCD 12A. A position on which the active stylus 2
contacts is detected by the touch panel 12B.
[0032] The wireless communication device 107 is a device that
executes wireless communication such as wireless LAN and 3G mobile
communication. The EC 108 is a single-chip micro computer
comprising a power circuit 108A for power management. The EC 108
comprises a function to power on/off the tablet device 1 in
accordance with the operation of a power button by a user.
[0033] The power-transmitting circuit for wireless power
transmission 109 is a circuit that transmits power from the power
circuit 108A to the active stylus 2 by use of the
power-transmitting coil 110. The power-transmitting coil 110 is a
coil that generates magnetic flux for resonating the
power-receiving coil of the active stylus 2 under control of the
power-transmitting circuit for wireless power transmission 109.
[0034] FIG. 3 is an exemplary diagram illustrating the system
configuration of the active stylus 2.
[0035] As shown in FIG. 3, the active stylus 2 comprises a
power-receiving coil 201, a power-receiving circuit for wireless
power transmission 202, a charge/discharge circuit 203 and an
active stylus configuration circuit 204.
[0036] The power-receiving coil 201 is a coil that generates power
by resonating by magnetic flux from the power-transmitting coil 110
of the tablet device 1. The power-receiving circuit for wireless
power transmission 202 is a circuit that stabilizes power generated
by the power-receiving coil 201 and supplies it to the
charge/discharge circuit 203. The charge/discharge circuit 203 is a
circuit that comprises a secondary battery or an electric
double-layer capacitor (hereinafter referred to as secondary
battery/electric double-layer capacitor 203A). The charge/discharge
circuit 203 charges the secondary battery/electric double-layer
capacitor 203A with power supplied from the power-receiving circuit
for wireless power transmission 202 and supplies the power of the
secondary battery/electric double-layer capacitor 203A to the
active stylus configuration circuit 204 as power for operation.
Thus, the active stylus 2 functions as an input device upon the
active stylus configuration circuit 204 operates by use of the
secondary battery/electric double-layer capacitor 203A as a power
source, and the secondary battery/electric double-layer capacitor
203A is charged with power from the power circuit 108A of the
tablet device 1. In the wireless power-transmission system, the
arrangement of the power-receiving coil 201 is devised so that
power transmitted from the tablet device 1 is efficiently received
in the active stylus 2, which will be described in detail
later.
[0037] FIG. 4 is an exemplary drawing illustrating an example where
the power-transmitting coil 110 in the tablet device 1 is arranged.
In FIG. 4, it is assumed in both (A) and (B) that the inside of the
tablet device 1 is viewed from the upper portion of the tablet
device 1.
[0038] In FIG. 4, (A) illustrates an example where the
power-transmitting coil 110 is arranged so as to encircle the whole
region of the upper surface of the main body 11, with which the
touch screen display 12 is overlapped. On the other hand, (B)
illustrates an example where the power-transmitting coil 110 is
arranged so as to encircle a partial region of the upper surface of
the main body 11, with which the touch screen display 12 is
overlapped. In either (A) or (B), magnetic flux orthogonal to the
upper surface of the main body 11 with which the touch screen
display 12 is overlapped is generated in a region encircled by the
power-transmitting coil 110. In the following, an orientation that
a region encircled by a coil faces is referred to as a coil
orientation.
[0039] FIG. 5 is an exemplary drawing illustrating an example where
the power-receiving coil 201 in the active stylus 2 is arranged. It
is assumed that the inside of the active stylus 2 is viewed from
the side surface portion of the active stylus 2.
[0040] As shown in FIG. 5, the power-receiving coil 201 is arranged
in, for example, the rear end portion of the active stylus 2 so
that the region encircled by the power-receiving coil 201 faces a
direction (direction of the side surface portion) orthogonal to the
axis of the active stylus 2. That is, the power-receiving coil 201
is arranged in an orientation orthogonal to the axis of the active
stylus 2. While it is exemplified that the power-receiving coil 201
is arranged in the rear end portion of the active stylus 2, where a
space is likely to be secured, it is not limited thereto; if there
is a space, the power-receiving coil 201 may be arranged in the
center end portion or the front portion of the active stylus 2.
[0041] The orientation of the power-receiving coil 201 arranged as
shown in FIG. 5 varies depending on how the active stylus 2 is
placed (with the axis horizontal [tilted]). Next, in view of this,
the desirable positional relationship between the
power-transmitting coil 110 of the tablet device 1 and the
power-receiving coil 201 of the active stylus 2 will be described
with reference to FIG. 6.
[0042] In FIG. 6, reference number 300 represents magnetic flux
generated by the power-transmitting coil 110 of the tablet device
1. It is desirable that the power-receiving coil 201 of the active
stylus 2 exist in an orientation perpendicularly intersecting the
magnetic flux 300. Typically, on the region encircled by the
power-transmitting coil 110, it is possible to place the
power-receiving coil 201 (power-receiving coil 201 [A]) in an
orientation perpendicularly intersecting the magnetic flux 300
generated by the power-transmitting coil 110, by being positioned
in the same orientation as the power-transmitting coil 110, i.e.,
in parallel with the power-transmitting coil 110. It is also
possible to place the power-receiving coil 201 in an orientation
perpendicularly intersecting the magnetic flux 300 generated by the
power-transmitting coil 110, by being positioned on a line
horizontal to the power-transmitting coil 110 (power-receiving coil
201 [B]).
[0043] As described above, the power-transmitting coil 110 of the
tablet device 1 is arranged so as to generate magnetic flux
orthogonal to the upper surface of the main body 11, with which the
touch screen display 12 is overlapped. In other words, the
power-transmitting coil 110 is arranged in an orientation
orthogonal to the screen of the touch screen display 12. The
wireless power-transmission system makes the power-receiving coil
201 of the active stylus 2 parallel to the power-transmitting coil
110 of the tablet device 1 when the active stylus 2 is placed on
the touch screen display 12. Further, even when the active stylus 2
is placed in the peripheral portion of the tablet device 1, the
wireless power-transmission system makes it possible to efficiently
receive power transmitted from the tablet device 1 by arranging the
power-receiving coil 201 so as to be positioned on a line
horizontal to the power-transmitting coil 110, if the active stylus
2 is placed on a position where the amount of magnetic flux from
the power-transmitting coil 110 intersecting the power-receiving
coil 201 is sufficient.
[0044] (Pattern 1)
[0045] To begin with, the first arrangement pattern of the
power-receiving coil 201 in the active stylus 2 will be described
with reference to FIG. 7.
[0046] As shown in (A) of FIG. 7, it is assumed that a clip portion
21 is attached to the active stylus 2. It is also assumed that the
main body portion of the active stylus 2 is cylindrical.
[0047] For example, when placed on the touch screen display 12 of
the tablet device 1, the active stylus 2 rotates around its axis to
make the clip portion 21 contact the touch screen display 12. (B)
of FIG. 7 is an exemplary cross-sectional view (orthogonal to the
axis) in the clip portion 21 of the active stylus 2.
[0048] When the screen of the touch screen display 12 is referred
to as line C, line C is contacted by the main body portion of the
active stylus 2 and the clip portion 21. A state where the clip
portion 21 contacts the touch screen display 12 includes two
possible states: one is that the left end portion of the clip
portion 21 contacts the touch screen display 12; and the other is
that the right end portion of the clip portion 21 contacts the
touch screen display 12. Line A represents the screen of the touch
screen display 12 on the assumption that the touch screen display
12 is contacted by the end portion opposite the clip portion 21.
The intersection point of these two lines A and C is referred to as
B.
[0049] In addition, the center of the cross-section, i.e., axis, of
the active stylus 2 is referred to as P, and a line including
segment BP is referred to as line E. A line including the
cross-section of the power-receiving coil 201 (a surface orthogonal
to the orientation of the power-receiving coil 201) is referred to
as line D.
[0050] At this time, the power-receiving coil 201 is arranged to
make line D parallel to line C so that the relationship of the
following formula (1) is satisfied:
.angle.ABC=2PBC=2.angle.EPD formula (1)
[0051] When the active stylus 2 is placed on the touch screen
display 12 of the tablet device 1 as shown in FIG. 8, for example,
line C is more likely to be contacted by the main body portion and
the clip portion 21 of the active stylus 2, by arranging the
power-receiving circuit for wireless power transmitting 202, the
charge/discharge circuit 203 and the active stylus configuration
circuit 204 in view of weight balance.
[0052] When the active stylus 2 in which the power-receiving coil
201 is thus arranged is placed on the touch screen display 12 of
the tablet device 1 as shown in FIG. 8, for example, the
power-transmitting coil 110 of the tablet device 1 is positioned
parallel to the power-receiving coil 201 of the active stylus 2.
Therefore, power transmitted from the tablet device 1 is
efficiently received in the active stylus 2.
[0053] Accordingly, for example, when using the active stylus 2, it
is possible to operate the active stylus 2 while transmitting power
only by placing the active stylus 2 on the touch screen display 12
of the tablet device 1 during a handwritten input operation.
[0054] Even if line A is contacted by the main body portion and the
clip portion 21 of the active stylus 2 as shown in (B) of FIG. 7,
the power-transmitting coil 110 of the tablet device 1 is not
positioned orthogonal to the power-receiving coil 201 of the active
stylus 2. This never leads to a situation where power transmitted
from the tablet device 1 is not received at all by the active
stylus 2.
[0055] (Pattern 2)
[0056] Next, the second arrangement pattern of the power-receiving
coil 201 in the active stylus 2 will be described with reference to
FIG. 9.
[0057] As with the above-mentioned first arrangement pattern, it is
assumed that the clip portion 21 is attached to the active stylus 2
and that the main body portion of the active stylus 2 is
cylindrical, as shown in (A) of FIG. 7. In the second arrangement
pattern, two power-receiving coils 201 [1] and [2] are arranged in
the active stylus 2.
[0058] In FIG. 9, the power-receiving coil 201 [1] is the
power-receiving coil 201 arranged in the same way as the
above-mentioned first arrangement pattern and the power-receiving
coil 201 [2] is the power-receiving coil 201 arranged in addition
to the above-mentioned first arrangement pattern. A line including
the cross-section of the power-receiving coil 201 [2] (a surface
orthogonal to the orientation of the power-receiving coil 201 [2])
is referred to as line F.
[0059] At this time, the power-receiving coils 201 [1] and [2] are
arranged to make line D parallel to line C and to make line F
parallel to line A so that the relationship of the following
formula (2) is satisfied:
.angle.ABC=2.angle.PBC=2.angle.EPD=2.angle.EPF formula (2)
[0060] When the active stylus 2 in which the power-receiving coils
201 [1] and [2] are thus arranged is placed on the touch screen
display 12 of the tablet device 1 as shown in FIG. 8, for example,
the power-transmitting coil 110 of the tablet device 1 is
positioned parallel to one of the power-receiving coils 201 [1] and
[2] of the active stylus 2, when either line A or C is contacted by
the main body portion and the clip portion 21. Therefore, power
transmitted from the tablet device 1 is efficiently received in the
active stylus 2.
[0061] Accordingly, for example, when using the active stylus 2, it
is possible to operate the active stylus 2 while transmitting power
only by placing the active stylus 2 on the touch screen display 12
of the tablet device 1 during a handwritten input operation.
[0062] If a plurality of power-receiving coils 201 are arranged in
the active stylus 2, all of the power-receiving coils may be
connected to the power-receiving circuit for wireless power
transmission 202, or, for example, one of them may be connected to
the power-receiving circuit for wireless power transmission 202.
The power-receiving coils 201 that are not connected to the
power-receiving circuit for wireless power transmission 202 play a
role in resonating the power-receiving coils 201 that are connected
to the power-receiving circuit for wireless power transmission
202.
[0063] (Pattern 3)
[0064] Subsequently, the third arrangement pattern of the
power-receiving coil 201 in the active stylus 2 will be described
with reference to FIG. 10.
[0065] (A) of FIG. 10 is a cross-sectional view (orthogonal to the
axis) of the active stylus 2. As shown in (A) of FIG. 10, it is
assumed that a surface parallel to the axis direction is formed in
the side surface portion of the active stylus 2.
[0066] The active stylus 2 is usually placed with the surface
formed in the side surface portion downward so that the stylus does
not roll over. Alternatively, the active stylus 2 rotates on its
axis, with the surface formed in the side surface portion downward.
That is, for example, when the active stylus 2 is placed on the
touch screen display 12 of the table device 1, the surface formed
in the side surface portion contacts the touch screen display
12.
[0067] In (B) of FIG. 10, line A represents the screen of the touch
screen display 12 and line B represents a line including the
cross-section of the power-receiving coil 201 (a surface orthogonal
to the orientation of the power-receiving coil 201). At this time,
the power-receiving coil 201 is arranged so that line B is parallel
to line A.
[0068] When the active stylus 2 in which the power-receiving coil
201 is thus arranged is placed on the touch screen 12 of the tablet
device 1 as shown in FIG. 8, for example, the power-transmitting
coil 110 of the tablet device 1 is positioned parallel to the
power-receiving coil 201 of the active stylus 2. Therefore, power
transmitted from the tablet device 1 is efficiently received in the
active stylus 2.
[0069] Accordingly, for example, when using the active stylus 2, it
is possible to operate the active stylus 2 while transmitting power
only by placing the active stylus 2 on the touch screen display 12
of the tablet device 1 during a handwritten input operation.
[0070] (Pattern 4)
[0071] Then, the fourth arrangement pattern of the power-receiving
coil 201 in the active stylus 2 will be described with reference to
FIG. 11.
[0072] FIG. 11 is an exemplary cross-sectional view (orthogonal to
the axis) of the active stylus 2. That is, it is assumed that the
active stylus 2 has the shape of a hexagonal prism.
[0073] When the active stylus 2 is placed on the touch screen 12 of
the tablet device 1, for example, any one of six surfaces formed in
the side surface portion contacts the touch screen display 12.
[0074] Therefore, as shown in FIG. 11, three power-receiving coils
201 are arranged so that each power-receiving coil 201 is parallel
to each surface formed in the side surface portion. More
specifically, each one of the receiving coils 201 is parallel to
each of three pairs of opposing surfaces in the six surfaces formed
in the side surface portion.
[0075] When the active stylus 2 is placed on the touch screen 12 of
the tablet device 1 as shown in FIG. 8, for example, even if any of
the surfaces contacts the touch screen display 12, the
power-transmitting coil 110 of the tablet device 1 is positioned
parallel to any one of the power-receiving coils 201 of the active
stylus 2. Therefore, power transmitted from the tablet device 1 is
efficiently received in the active stylus 2.
[0076] Accordingly, for example, when using the active stylus 2, it
is possible to operate the active stylus 2 while transmitting power
only by placing the active stylus 2 on the touch screen display 12
of the tablet device 1 during a handwritten input operation.
[0077] In the above-mentioned case, the active stylus 2 is placed
on the touch screen display 12 of the tablet device 1 as shown in
FIG. 8. In the following case, the active stylus 2 is placed in the
side surface portion of the tablet device 1 as shown in, for
example, FIG. 12.
[0078] When the active stylus 2 which has been described above is
placed on, for example, the same table as the one on which the
tablet device 1 is placed, the power-transmitting coil 110 of the
tablet device 1 is positioned parallel to the power-receiving coil
201 of the active stylus 2. Also, as described with reference to
FIG. 6, the power-receiving coil 201 can be positioned in an
orientation perpendicularly intersecting the magnetic flux 300
generated by the power-transmitting coil 110 by positioning the
active stylus 2 on a line horizontal to the power-transmitting coil
110 (if the active stylus 2 is placed on a position where the
amount of magnetic flux from the power-transmitting coil 110
intersecting the power-receiving coil 201 is sufficient).
[0079] Therefore, as shown in FIG. 13, power transmitted from the
tablet device 1 can be efficiently received by the active stylus 2,
further by arranging the power-receiving coil 201 in the active
stylus 2 so as to be positioned on a line horizontal to the
power-transmitting coil 110.
[0080] For example, when an accommodation portion for accommodating
the active stylus 2 is provided in the housing side surface portion
of the tablet device 1 and the active stylus 2 is accommodated in
this accommodation portion, the power-receiving coil 201 may be
positioned on a line horizontal to the power-transmitting coil 110.
Also, when both the tablet device 1 and the active stylus 2 are
accommodated in a cover, a holder or the like that can accommodate
them, the power-receiving coil 201 may be positioned on a line
horizontal to the power-transmitting coil 110.
[0081] As shown in, for example, FIG. 14, an angle and a distance
are made between the power-transmitting coil 110 and the
power-receiving coil 201 on the touch screen display 12 of the
tablet device 1, during a handwritten input operation by use of the
active stylus 2. Therefore, the amount of magnetic flux from the
power-transmitting coil 110 intersecting the power-receiving coil
201 decreases and the power-transmission efficiency decreases.
However, if the amount of operating power of the active stylus 2 is
equivalent to or smaller than the amount of receiving power, the
active stylus 2 can be operated or can charge the secondary
battery/electric double-layer capacitor 203A by power transmitted
from the tablet device 1.
[0082] As described above, the wireless power-transmission system
realizes operating a stylus while transmitting power.
[0083] The various modules of the systems described herein can be
implemented as software applications, hardware and/or software
modules, or components on one or more computers, such as servers.
While the various modules are illustrated separately, they may
share some or all of the same underlying logic or code.
[0084] While certain embodiments have been described, these
embodiments have been presented by way of example only, and are not
intended to limit the scope of the inventions. Indeed, the novel
embodiments described herein may be embodied in a variety of other
forms; furthermore, various omissions, substitutions and changes in
the form of the embodiments described herein may be made without
departing from the spirit of the inventions. The accompanying
claims and their equivalents are intended to cover such forms or
modifications as would fall within the scope and spirit of the
inventions.
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